The present invention relates to overhead conveyors of the type disclosed in U.S. Pat. No. 5,806,655 issued Sep. 15, 1998 to Tabler, in U.S. Pat. No. 5,785,168 issued Jul. 28, 1998 to Beall, Jr., in U.S. Pat. No. 4,203,511 issued May 20, 1980 to Uhing, in U.S. Pat. No. 3,164,104 issued Jan. 5, 1965 to Hunt, and in U.S. Pat. No. 3,850,280 issued Nov. 26, 1974 to Ohrnell.
In this type of overhead conveyer, one or a plurality of aligned rotatable shafts extend along the conveying path, and skewed rollers contact the upper portion of such shafts to be driven linearly along the path as the shafts rotate, with the rollers carrying a depending carriage for supporting the conveyed objects or loads. One or more powered drive units are arranged along the conveying path to drivingly rotate the shaft or shafts. This type of conveyor is specifically designed for a particular environment, and therefore the location and number of drive units, as well as the spacing therebetween, varies according to the conveyor environment. A considerable amount of installation time is taken on site in assembling and mounting the drive units and in replacing them should a drive unit fail.